Filing drawer



F. A. SCHMITZ V June 4, 1935.

FILING DRAWER Filed March 24, 1934 INVENTOR ATTORNEY,

Patented June 4, 1935 UNITED STATES PATE FILING DRAWER Fred A. Schmitz, CincinnatL'Ohio, assignor to The Globe-Wernicke Company, Nor-wood, Ohio,

a corporation of Ohio Application March 24, 1934, Serial No. 717,205 A Claims.

This invention relates to drawers of the character used in filing cabinets, and is particularly directed to an improved carriage construction for slidably supporting a drawer of this type. This 5 improvement is primarily adaptable to metallic filing cabinets, although it can be embodied in other types of furniture.

The carriage construction to which the present improvements are directed may be referred to as an extension drawer slide. The carriage incorporates rollers and wheels for free movement within the stationary guide channels of the cabinet frame. Wheels are provided respectively at the lower outer end of the carriage and at the upper rear end of the carriage engaging the lower tracks and the upper tracks of the stationary guides respectively. Intermediate rollers are provided slightly back from position intermediate the length of the slide, these rollers engaging the lower tracks of the guide channels. The drawer through side rails is supported on forward wheels and intermediate rollers, other wheels being provided just above the intermediate rollers for preventing tipping of the drawer when open. I 0

It is the object of the present invention to provide improved intermediate rollers and mount-. ings therefor for supporting a carriage in the stationary guides and'the drawer on the carriage, each of which rollers is held in substantially fixed axial position and maintained in proper lateral spacing by a device which greatly reduces the friction. Through these devices the rollers are restrained to proper position on the carriage without imposing frictional resistance to their rolling movement. At the same time there is great advantage when the support rail of the drawer and the stationary guide rail are out of alignment or are irregular for any reason, in that the devices permit compensating tipping or cantingof the rollers without causing friction.

Other objects and further advantages will be more fully apparent from a description of the accompanying drawing, in which: 7

Figure 1 is a perspective view of a filing cabinet incorporating the present improvements, a portion of the cabinet being broken away and a drawer partly opened for illustrating the carriage." Figure 2 is a fragmentary sectional view taken lengthwise of the guide and looking toward the carriage and drawer, showing the drawer fully opened.

Figure3 is'alongitudinal sectional view taken I through the stationary guide and the support 0' ed in and between theadjacent guides.

rail of the drawer, looking away from the drawer and showing the relation of the wheels and rollers.

Figure 4 is a sectional view taken on 1ine4--4, Figure 1, detailing the improved mounting for a floating roller. 0

Figure 5 is a side view of the improved roller construction.

Figure 6 is a sectional view taken on line 66, Figure 5, showing the proportionate widths of 1 the roller and the retaining device orhub.

Referring to the drawing, a filing cabinet is generally indicated at I0. In the type of cabinet. shown, the drawers l lare vertically stacked, that is to say, they are mounted on respective slide 1 support means-in superimposed -positions.- The cabinet is of rectangular horizontal cross section and has an open front.

A pair of guide channels I2 are provided for each drawer. In the instance of each drawer a guide channel is fixed in horizontal position against the inner side of each side wall of the cabinet with the guides facing each other. A carriage l3 or extension drawer slide 13 is mount- The drawer II is slidably supported on this carriage or slide. l

Specifically described, the carriage incorporates inwardly facing channel shaped side pieces l4 and connecting bars or rails I5. These side rails fit loosely in the guide channels I2 and have. a rolling engagement therewith through sets of rollers and wheels of the following nature and arrangement:

At the lower portion of each side of the forward end of the carriage, a roller bearing wheel 16 is provided. The axle of the wheel is fixed in and between the side rail vertical wall and a bracket H. The lower flange of the side rail is notched as at. Hi to provide clearance for the wheel which projects beyond this fiange and is in contact with the lower track orfiange' of the fixed guide channel. Intermediate of the length of the carriage, loose rollers iii are provided, one at each side of the carriage having a rolling contact with the lower fiange or track of the fixed guide. These rollers will be described in detail, and their mounting will be fully set forth hereinafter. l i

At the upper portion of each side of the rear end of the carriage, ball bearing wheels 20 are provided, one at each side or in each side rail mounted in the same manner as those at the forward end except that the rear wheels project through clearance slots 2| in the upper flanges guides.

7 ing the load on their axles.

of the carriage side rail and are adapted to have engagement with the upper flanges or tracks of the fixed guides. Just above the intermediate rollers, ball bearing wheels 22 are provided spaced slightly therefrom and journalled in the carriage side rails by means of journal brackets 23 in the same manner as the front and rear wheels. V

The drawer includes support rails 24 secured longitudinally along the lower edges thereof. These rails are engaged on the forward wheels .5 6

and intermediate rollers IQ of the carriage pass-' ing between the intermediate rollers and the ad-'j jacent wheels 22!. A down-turned lip 25 is provided on each rail betweenthe rollers and wheels and the vertical wall of the carriage side rails.

As has been mentioned, it is an inherent function of this carriage and drawer combination that the drawer will move out at twice the speed of the carriage, so that the slide is extended fromthe cabinet for supporting the drawer when fully opened. There are stops 28 provided on the carriage which engage the ends of slots 23 in the lower flanges of the stationary guides I2 for limiting the movement of the carriage. Cooperating stops 26, 21, are provided on the drawer and the carriage respectively so that when the drawer is fully withdrawn contact or abutment is made for limiting further withdrawal.

When thedrawer is fully closed, it rests on the fioatingrollers l9 and the outer wheels I6 which are engaged on the .lower tracks of the When the wheels l5, move off the tracks as the drawer is being initially opened, the drawer is still suported. on the rollers 19 and wheels i6, although the wheels l6 are now tak- As this occurs the rear wheels through their axles take the load, as the carriage tends to rock on the intermediate rollers, and engage the upper tracks of the guides, whereby the carriage is supported despite the movement of its front wheels from support. When there is a tendency for the drawer to rock on the forward wheels, the intermediate upper wheels 22 are effectively engaged by the rails of the drawer although this seldom occurs since the drawer cannot move outwardly far enough to over-balance in relation to the wheels Hi. It is believedthat it will be apparent that the intermediate lower rollers are at work or carry load substantially at all times. 7 7

Accordingly, it is important that these rollers [9 be maintained in definite relation to the car-V riage with as little friction as possible. For this purpose the following structure is provided.

Referring to each roller, a bracket 29 is fixed against the inner face of the vertical wall of the carriage side rail. This bracket includes a pressed-out portion providing clearance for the roller between the pressed-out portion and the 7 wall of the side rail.

A hub element 45} including axially extended studs 4! is mounted between the bracket and the wall of the side rail. As shown in Figure 4, the vertical wall of the side rail is pressed out to provide longitudinal portions 42 spaced from the vertical wall of the fixed guide. The portions provide clearance for the axial supports of the wheels and the studs of the retaining devices for the central rollers. The studs are flattened out at diametrically opposite portions of their peripheries and are projected through vertical slots 53 in the vertical wall of the carriage side rail and the bracket wall. The centering element or hub 49 is tree to move vertically, but is held againstrotation by the engagement of the flattened stud portions with the slot edges. This hub element or centering element has an axial dimension causing it to fit snugly between the bracket and the side rail of the carriage. The roller is in the form of a shell or sleeve which is of less width or axial dimension than the hub element so that there is a clearance between each side thereof and the adjacent bearing bracket and side rail.

opposingly related annular grooves Ml are provided in the outer and inner peripheries of the hub element and the roller, and a series of balls 5 are circumferentially arranged in and between these grooves.v

Now it is pointed out that these rollers are not supported on their axes but rather carry the load at opposite sides of their periphery. Therefore, they are unlike wheels and are accurately referred to as rollers. It will be noted that the inner element is not supporting the outer element but is merely maintaining the outer element in'a fixed position longitudinally of the carriage and transplace in case the track or the rail of the drawer.

is not accurately horizontally disposed. 7 Any, tendency of the roller to shift longitudinally of the carriage causes the roller to bear against the balls for the most elficient frictionless contact. Assuming that the rollers were solid, this tendency to shift longitudinally would cause the;

studs to bear under considerable pressure against the sides of the slots and frictional'bind' and wear would occur.

, Also, in the prior construction, if a roller should;

be tipped from horizontal axialposition, its sides wouldv engage against either the bracket or the guide rail with the result of loss of efliciency'due to friction. As designed, this tipping cantake place up to a certain degree on the balls without interfering with the free movement of the rollers,-

and without causing contact since clearance is provided.

The absolute freedom of these intermediate rollers is essential to free movement of the drawer and by the present construction this freedom is always possible. Accordingly, an improved mounting has been provided for the rollers for maintaining the same in definite rolling relation to the carriagewithout causing friction. Having described my invention, I calim:

1. In a drawer slide construction, a carriage,

xed channels for guiding and supporting said carriage, wheels at the forward end of the carriage operating on the lower flanges of said channels, rollers journalled in the carriage intermediate of its length operating on said lower flanges, a drawer having side rails resting on said rollers and wheels, a hub element mounted in the carriage axially of each roller, and balls interposed between the hub element and the roller, each roller having lateral clearance in relation to the carriage.

2. In combinationwith a drawer and its casing, channel shaped guides fixed in the casing in opposing relation, a rectangular carriage adapted for movement within and between said guides,'a wheel mounted at each corner cf said carriage, the forward wheels adapted to engage on the lower flanges of said guides and the rear wheels adapted to engagethe upper flanges of said guides,

intermediate rollers J'ournalled in said carriage in engagement with the lower flanges of said guides, said drawer having support rails engaged on said forward wheels and intermediate rollers, guide wheels engaging said drawer for maintaining it on said rollers, each of said rollers including an inner cylindrical element fixed in said carriage against axial movement, an outer sleeve element of less axial length than said inner element and balls circumferentially arranged between said inner and outer elements, whereby said outer element is free to tip and inward radial thrusts are taken by the balls.

3. In combination with a drawer and its casing including channel guide rails, a carriage having wheels mounting it on and between said guide rails, intermediate rollers in said carriage, said drawer mounted for rolling movement on said intermediate rollers and certain of the wheels of said carriage, said rollers having axially arranged retainers mounted in the carriage and anti-friction elements between said rollers and retainers for maintaining said rollers in definite relation to the carriage without interfering with free rotative movement thereof.

4. In combination with a drawer and its casing, channel shaped guides fixed in the casing in opposing relation, a rectangular carriage adapted for movement within and between said guides, a wheel mounted at each corner of said carriage, the forward wheels adapted to engage on the lower flanges of said guides and the rear wheels adapted to engage the upper flanges of said guides, intermediate rollers journalled in said carriage in engagement with the lower flanges of said guides, said drawer having support rails engaged on said forward wheels and intermediate rollers, guide wheels engaging said drawer for maintaining it on said rollers, each of said intermediate rollers having a hub element including axial studs vertically slidably and non-rotatively mounted in said carriage, said carriage including portions engaging the ends of said hub element for preventing axial play thereof, said rollers mounted on said hub elements, and balls interposed between said hub elements and said rollers, said rollers having less axial length than the hub elements.

5. In a drawer slide construction, a carriage, fixed channels for guiding and supporting said carriage, wheels at the forward end of the carriage operating on the lower flanges of said channels, rollers journalled in the carriage intermediate of its length operating on said lower flanges, a drawer having side rails resting on said rollers and wheels, guide wheels in said carriage engaging said side rails adjacent to and on the opposite side from saidrollers, a hub element non-rotatively mounted in the carriage axially of each roller, and balls interposed between the hub element and the roller, each roller having lateral clearance in relation to the carriage.

FRED A. SCHMITZ. 

